Wednesday, March 28, 2012

Town of Cape Vincent Zoning Ordinance Revision Committee discusses setbacks necessary to protect citizens against wind turbine blade tip throw.

Yesterday's Town of Cape Vincent Zoning Ordinance Revision Committee was attended by three people from the Town of Lyme and JLL.

The Town of Cape Vincent's engineer, Kris D. Demmick of Bernier and Carr & Associates joined the committee's discussion on the establishment of setbacks necessary in the new ordinance for the protection of the health and safety of all Town of Cape Vincent residents and homeowners against the possibility of object throw from proposed wind turbines.

Kris started the discussion with the recommendation that all setbacks be measured from the landowners' property line no matter what the size of the parcel is. This recommendation would be instead of measuring the setbacks from inhabited dwellings.

He presented the committee with two charts. One that defines the mathematically calculated turbine blade tip throw capability of a large industrial turbine typical of what is proposed for the Town of Cape Vincent and for a typical small personal use turbine that is available commercially. His information showed that an industrial wind turbine, at around sixteen rpm would have the potential,  under ideal conditions, to throw an object well over two thousand feet. One committee member pointed out that most wind turbine failures that result in thrown debris are "run-away situations" where the braking device has failed, causing, higher rpms, higher tip speeds and consequently, the potential for longer throw distances. 

One of Demmick's charts showed that small personal turbines, such as the popular Burgey 10 kW Models, have the calculated potential of throwing an object over seven thousand feet. That is because of the potential for much higher rpms. The smaller, less sophisticated in design, turbines do not have a gear box or braking system that effectively controls the speed. However, Demmick added that although such throw distances were mathematically possible they were improbable because  the aerodynamics of most objects or debris would cause them to "flutter" and reduce the distances they could travel. He demonstrated that phenomenon by taking a business card out of his pocket and flinging it. The card immediately lost aerodynamic stability and fell to the floor after about six feet.

It happens far more often than developers like
British Petroleum and their local proponents
will ever admit.
One committee person expressed concerns that the new zoning law should not only protect the neighbor's from wind turbine failures and other situations, where they could throw objects, but also the people living with the personal turbine. For that reason, he recommended that the town require a factory certified inspection of the installation of all personal turbines before they are used.

The committee's feeling was that personal use turbines could pose far greater concerns for the town because of their "do-it-yourself" mentality that often overlooks and avoids expensive, but professional advise. One committee member pointed out that the recently installed personal turbine on Tibbetts Point road was, in many respects, done properly if not even with a bit of "design and construction overkill".

Another committee member suggested soliciting the advice of the Town's Fire Chief who is   ultimately involved with all town safety and emergency situations.

Demmick pointed out that personal wind turbines have a tendency to break down internally after relatively short periods of use. He said he has seen many abandoned around the county. It was further suggested that for the safety and health of all citizens,  the town require regularly scheduled follow up inspections of personal turbine installations.

Demmick pointed out that for most homes, a 10 kW personal turbine would be sufficient for power. He commented that he got along just fine during the ice storm with a 2k gasoline generator. He added that when the personal turbines are connected to the pubic supply, National Grid does not allow a customer to produce anymore electricity than that needed by your home in a given year. Anything more is wasted meaning that it would be useless to install a personal turbine that generated excess. My understanding of Demmick's explanation is that any extra electricity produced by personal turbines can't be sold back to National Grid.

After telling the committee that he has seen many abandoned personal turbines around the county, he said  that one available model of personal turbines had a shroud built around it as a safety device. The question was, "How would setbacks be fair to such a device?" The town's zoning officer, serving as a member of the committee, commented, "that is where the homeowner wanting that kind of safer personal turbine would apply to the ZBA for a variance."

Members of the Town of Cape Vincent Zoning Board of Appeals are serving on the Zoning Ordinance Revision Committee and were involved in the personal wind turbine discussions.

For the purpose of zoning and safety-health setbacks, the committee and the town engineer discussed the possibility of classifying wind turbines into three categories. (1) personal home use, (2) farm-commerical business use and (3) industrial electricity production use such as that proposed for the town by British Petroleum.

British Petroleum has already proposed a project which asks for industrial wind turbine setbacks that are far less than those described in the technical recommendations submitted to the committee by the town engineer.